1. Field of the Invention
The present invention concerns a muffler for an internal combustion engine. In particular, the present invention concerns a linear muffler designed to be mounted in the exhaust system of an automobile to suppress the shockwaves in the exhaust system.
2. Prior Art
Virtually all internal combustion engines, whether for a lawnmower or for an automobile, require a muffler to suppress the shockwaves caused by exhausting the spent fuel-air mixture from the chamber of each reciprocating piston. Conventional design of an exhaust system includes an exhaust pipe which is directly coupled to each piston chamber and which in turn is coupled to a muffler.
Conventional exhaust pipes are cylindrical in design because it is the most economical shape with respect to material usage per internal volume. For this reason, exhaust pipes have uniformly been circular in cross-section and will presumably continue to be so. However, the cylindrical cross- sectional shape of an exhaust pipe does not aid in significantly suppressing the plurality of shockwaves generated by the internal combustion engine. In fact, shock waves generally travel in a conical shape and the cylindrical cross-section of an exhaust pipe does not suppress the shockwave. This is easily evidenced by the fact that the resultant sound of a disconnected muffler is significantly louder than with a connected muffler.
Conventional muffler design has merely been to increase the cross-sectional area of the exhaust system emerging from the cylindrical cross-section of the exhaust pipe, thus greatly reducing the speed which the shockwave travels through the muffler. Additionally, the muffler includes a plurality of baffles generally consisting of partially extending walls across the interior of a conventional muffler to break up the shockwaves, thereby reducing the noise level. Typically, the conventional muffler is circular in shape, like the exhaust pipe, or it may sometimes be oval in shape. While these exhaust pipes are minimally acceptable for reducing the shockwave and thereby reducing the resultant sound, these mufflers are expensive to manufacture due to the plurality of partial walls within the muffler and due to the material requirements and necessary labor intensive manufacturing steps.
Accordingly, one of the chief aims of the present invention is to produce a muffler which is capable of being formed with a reduced number of manufacturing steps.
Another aspect of the present invention is to construct a simpler muffler than conventional types which is capable of significantly reducing the shockwaves and the resulting sound.
Another aim of the present invention is to provide a new shape for a muffler which can easily be adapted to conventional exhaust systems of present day automobiles.
Another aim of the present invention is to provide a muffler having a shape that reduces the size of or omits the necessity for a cavity in the underside of an automobile for the muffler.
Another aspect of the present invention is to significantly reduce the shockwaves emitting from an internal combustion engine at least as well as or better than conventional mufflers, while employing less material usage in manufacturing the muffler as compared to conventional mufflers.